/*

 * Licensed to the Apache Software Foundation (ASF) under one

 * or more contributor license agreements.  See the NOTICE file

 * distributed with this work for additional information

 * regarding copyright ownership.  The ASF licenses this file

 * to you under the Apache License, Version 2.0 (the

 * "License"); you may not use this file except in compliance

 * with the License.  You may obtain a copy of the License at

 *

 *     http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

package com.bff.gaia.unified.runners.core.metrics;



import com.google.auto.value.AutoValue;

import com.bff.gaia.unified.sdk.annotations.Experimental;

import com.bff.gaia.unified.sdk.annotations.Experimental.Kind;

import com.bff.gaia.unified.sdk.metrics.MetricKey;

import com.bff.gaia.unified.vendor.guava.com.google.common.collect.Iterables;



import java.io.Serializable;

import java.util.Collections;



/** Representation of multiple metric updates. */

@Experimental(Kind.METRICS)

@AutoValue

public abstract class MetricUpdates {



  public static final MetricUpdates EMPTY =

      MetricUpdates.create(

          Collections.emptyList(), Collections.emptyList(), Collections.emptyList());



  /**

   * Representation of a single metric update.

   *

   * @param <T> The type of value representing the update.

   */

  @AutoValue

  public abstract static class MetricUpdate<T> implements Serializable {



    /** The key being updated. */

    public abstract MetricKey getKey();

    /** The value of the update. */

    public abstract T getUpdate();



    public static <T> MetricUpdate<T> create(MetricKey key, T update) {

      return new AutoValue_MetricUpdates_MetricUpdate(key, update);

    }

  }



  /** Returns true if there are no updates in this MetricUpdates object. */

  public boolean isEmpty() {

    return Iterables.isEmpty(counterUpdates()) && Iterables.isEmpty(distributionUpdates());

  }



  /** All of the counter updates. */

  public abstract Iterable<MetricUpdate<Long>> counterUpdates();



  /** All of the distribution updates. */

  public abstract Iterable<MetricUpdate<DistributionData>> distributionUpdates();



  /** All of the gauges updates. */

  public abstract Iterable<MetricUpdate<GaugeData>> gaugeUpdates();



  /** Create a new {@link MetricUpdates} bundle. */

  public static MetricUpdates create(

      Iterable<MetricUpdate<Long>> counterUpdates,

      Iterable<MetricUpdate<DistributionData>> distributionUpdates,

      Iterable<MetricUpdate<GaugeData>> gaugeUpdates) {

    return new AutoValue_MetricUpdates(counterUpdates, distributionUpdates, gaugeUpdates);

  }

}